Project will be continued and expanded to: include 1500 primary evaluations and 300 secondary evaluations per year; repeat evaluation of some category II substances and selected compounds which failed to exhibit anticonvulsant activity in the initial test; expand the toxicity profile on selected substances by including a dose range-effect study and the determination of a TD50 based on los of righting revles; include anticonvulsant tests based on known mechanisms of action to evaluate effect of the test substance on electrolyte transport and to determine effect of test substance on GABA mechanisms, hyponatremic EST, etc.; and evaluate the test substance in other laboratory species if it is felt that such information is essential to more precise evaluation of the test substance or is necessary on certain substances to eliminate the question of species sensitivity which continues to surface.